Which of the following is a primary function of an air handling unit in ventilation systems?

An air handling unit (AHU) is a crucial component of ventilation systems and primarily serves to filter air as one of its main functions. In the context of HVAC (heating, ventilation, and air conditioning), the air handling unit works to condition and circulate air throughout a building, ensuring that the air inside is clean, comfortable, and properly controlled for temperature and humidity.

Filtering air is essential because it removes airborne contaminants, dust, allergens, and other particles, contributing to better indoor air quality. This function is particularly important in environments where air quality is a priority, such as hospitals, schools, and commercial buildings. The AHU typically includes filters that can be changed or cleaned regularly to maintain optimal performance.

The other functions listed in the options are not related to the primary purpose of an air handling unit in ventilation systems. Heating water is a task managed by boilers; providing lighting is outside the scope of HVAC systems; and circulating chemicals is not a function associated with air handling units, as those would typically pertain to specific chemical handling systems.

In summary, the key function of an AHU in ventilation systems is to filter and condition the air being supplied to interior spaces, making it an essential component for maintaining air quality and comfort.